1. Field of the Invention
The present invention relates to a dust collecting device and method and, more particularly, to a device and method of collecting dust using highly charged hyperfine liquid droplets formed through an electro-hydrodynamic atomization process.
2. Description of the Prior Art
As well known to those skilled in the art, conventional dust collecting devices are classified into two types: electrostatic devices using electrostatic dust precipitators and filtering devices using dust filters. In an operation of the conventional dust collecting devices using the electrostatic participators, target dust is forced to pass through a corona discharge area laden with ions, thus being primarily charged with electricity. Thereafter, the electrically charged dust is exposed to an electric field, and so a desired dust collection effect is achieved. On the other hand, the conventional dust filtering devices using dust filters accomplish a desired dust collection effect by removing the dust using filters. The construction and operation of such conventional dust collecting devices are well known to those skilled in the art regardless of their types, and so further explanation is thus not deemed necessary.
The study of electro-hydrodynamic atomization (EHDA) that is sometimes called xe2x80x9cElectrosprayingxe2x80x9d has been long carried out. In addition, the formation of electrically charged hyperfine liquid droplets has been actively studied in recent years since a variety of industrial fields are very interested in the use of such liquid droplets. Electro-hydrodynamic atomizers have been preferably used for producing highly charged hyperfine liquid droplets. Such atomizers form desired highly charged hyperfine liquid droplets by exposing the droplets to an electric field having a high voltage difference. An example of such conventional electro-hydrodynamic atomizers is referred to U.S. Pat. No. 5,873,523. Hyperfine liquid droplets, produced by such a conventional electro-hydrodynamic atomizer, have a very small size of about several ten nanometers in addition to being highly charged with electricity. Such highly charged hyperfine liquid droplets have been preferably used as, for example, an ion source for mass analyzers.
However, the conventional dust collecting devices are problematic as follows:
That is, the electrostatic dust collecting devices may fail to effectively charge target dust with electricity when the dust has exceedingly hyperfine sizes, even though the devices are preferably operable at low cost due to low pressure drop of their electrostatic precipitators. When the target dust is not effectively charged with electricity as described above, it is almost impossible to electrostatically collect the dust. Another problem experienced with this type of device resides in that the device undesirably generates harmful ozone due to corona discharge.
On the other hand, the dust collecting devices using dust filters are advantageous in that they somewhat effectively remove dust having exceedingly hyperfine sizes. However, this type of device is problematic in that it is increased in its operational cost due to high pressure drop. Another problem with this type of device resides in that it is necessary to repeatedly clean the filter or to repeatedly replace the filter with a new one.
Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide a dust collecting device and method, which is designed to easily and effectively collect and remove dust using highly charged hyperfine liquid droplets formed through an electro-hydrodynamic atomization process.
Another object of the present invention is to provide a dust collecting device and method, which does not generate harmful ozone and is effectively operable at low cost in comparison with conventional dust collecting devices and methods.
In order to accomplish the above objects, the present invention provides a dust collecting device, comprising: a dust guide duct; one or more capillary within the dust guide duct and used for spraying liquid supplied from a liquid supply thereto; a voltage applying means for forming an electric field between the guide duct and the capillary, thus forming highly charged hyperfine liquid droplets sprayed from tip of the capillary; an electric insulating means formed on the external surface of the dust guide duct so as to intercept a voltage undesirably applied to the dust guide duct; a dust sucking means for sucking dust-laden air into the dust guide duct so as to allow dust to be absorbed by the highly charged hyperfine liquid droplets; and a dust collecting means detachably coupled to the dust guide duct while being electrically insulated from the duct, the dust collecting means forming an electric field having a polarity opposite to that of the highly charged hyperfine liquid droplets, thus electrostatically collecting and removing the dust absorbed by the highly charged hyperfine liquid droplets.
The present invention also provides a dust collecting method, comprising the steps of: forming highly charged hyperfine liquid droplets within a dust guide duct through an electro-hydrodynamic atomization process; sucking dust-laden air into the duct so as to allow dust to flow along with the highly charged hyperfine liquid droplets within the duct; absorbing the dust by the highly charged hyperfine liquid droplets; and collecting and removing the dust, absorbed by the highly charged hyperfine liquid droplets, by using dust collecting means, the dust collecting means forming an electric field having a polarity opposite to that of the highly charged hyperfine liquid droplets.